Plastic from CO₂, Water, and Electricity: Tandem Electrochemical CO₂ Reduction and Thermochemical Ethylene-CO...

Converting CO₂ into industrially useful products is an appealing strategy for utilization of an abundant chemical resource. Electrochemical CO₂ reduction (eCO₂R) offers a pathway to convert CO₂ into CO and ethylene, using renewable electricity. These products can be efficiently copolymerized by organometallic catalysts to generate polyketones. However, the conditions for these reactions are very different, presenting the challenge of coupling microenvironments typically encountered for the transformation of CO₂ into highly complex but desirable multicarbon products. Herein, we present a system to produce polyketone plastics entirely derived from CO₂ and water, where both the CO and C₂H₄ intermediates are produced by eCO₂R. In this system, a combination of Cu and Ag gas diffusion electrodes is used to generate a gas mixture with nearly equal concentrations of CO and C₂H₄, and a recirculatory CO₂ reduction loop is used to reach concentrations of above 11% each, leading to a current-to-polymer efficiency of up to 51% and CO₂ utilization of 14%.